[arizonafoxx]

Depending on the size of the motors you want to use and how you reduce the speed you could use spike relays, which would not require a micro to control them. This of course would cause the motors to either be full speed in fwd/rev or stopped, but if your robots full speed was something manageable like maybe 4ft per second that is totally plausible. All you would need is 5 volt inputs to the spikes which could easily come from buttons or other non-micro related circuitry. I have built a few robots like this. Tank drive is achieved but speed control is not desired.